Module to reshape vectors. The reshape operation includes the
possibility to:
<ul>
  <li>add one or more new columns to the vector table attribute</li>
  <li>convert the geometry into a derived geometry (from polygons to
points or to lines)</li>
  <li>delete from the vector table attribute</li>
</ul>
<br>
The reshape uses the <i>ECQL</i> language, please refer to the <a href="http://udig.refractions.net/confluence/display/EN/Common+Query+Language">
uDig user manual </a> or the <a href="http://docs.geotools.org/latest/userguide/library/cql/cql.html">
GeoTools documentation </a> for more informations about the syntax and
usability of the language.
<br>
<br>
<b>Geometry changing examples:</b>
<br>
To create a centroid layer from a polygon layer use:<br>
<br>
	the_geom=centroid(the_geom)<br>
<br>
To create a buffer of 20 meters from a points layer use:<br>
<br>
	the_geom=buffer(the_geom, 20.0)<br>
<br>
To create a convex hull from a points layer use:<br>
<br>
	the_geom=convexHull(the_geom)<br>
<br>
<b>Other examples:</b>
<br>
To create a two new field containing the perimeter and area of the
polygons in a layer:<br>
<br>
	area=area(the_geom)<br>
	length=geomLength(the_geom)<br>
<br>
This is also the perfect way to create a new column in a shapefile
layer and assign it a new default value:<br>
<br>
	newfield=-1<br>
<br>
<br>
<h3>Inputs</h3>
<ul>
  <li>the vector to reshape</li>
  <li>the ECQL reshape function</li>
  <li>the list of fields to remove, comma separated</li>
</ul>
<br>
<br>
<h3>Output</h3>
<ul>
  <li>the new derived vector</li>
</ul>